Electronic Design Automation (EDA) is the category of tools (e.g., computer programs) for designing and producing electronic systems ranging from printed circuit boards (PCBs) to integrated circuits. EDA is sometimes referred to as ECAD (electronic computer-aided design) or just CAD. Competitive pressures to produce new generations of products having improved functionality and performance in more efficient ways have motivated the growing importance of EDA. Further, the complexity of simulating certain electrical structures has increased over the past several years. With relatively high signal rates (e.g., 5-10 Gbit/s or more), the desire for complex and accurate models for components in electrical structures grows to ensure that the physical product performs as desired.
One example of an electrical structure that may benefit from accurate and complex models is a serial communications link (e.g., a backplane serial link). EDA models may help designers predict electrical metrics such as loss, reflection, crosstalk, and skew that may affect system operation. Further, designers may wish to have accurate models for the active and passive components of the serial link for design trade-off studies, for system budgeting and margin studies, and for component sensitivity analysis.
Continuing with the serial link example, to provide an accurate model for the serial link, models for the connectors, chips, packages, PCB traces (or “traces”), vias, and other components may be useful. To generate a model of an existing physical channel for a serial link, the channel may be coupled to a vector network analyzer (VNA) that is operative to measure the scattering parameters (or s-parameters) of the channel. Although this technique is useful for generating models of complete channels, it may be desirable in some applications to provide models of one or more components in the channel. As can be appreciated, it may be difficult to measure characteristics of certain components in the serial link channel, such as vias or other devices, due to various reasons including the inability to physically connect probes of a VNA to these components.